10/6/15

An Animal That "Sees" With its Ears! by Bert Thompson, Ph.D.


http://apologeticspress.org/apPubPage.aspx?pub=2&issue=781

An Animal That "Sees" With its Ears!

by Bert Thompson, Ph.D.
The animal kingdom—from ants to zebras—contains many strange yet wonderful creatures. But some of the most amazing of God’s creatures are those animals that "see" with their ears.
Most animals have very good eyesight. They use this eyesight to hunt for food. For example, owls have very large eyes, which they use to search for food at night. Cats, too, have eyes that open wider as it gets dark, so that they can hunt even at times when humans can barely see. The keen eyes of eagles can spot mice even from high up in the air.
But some animals have tiny eyes, and very poor eyesight. So how do they hunt for food? God has given them another way to "see," by using their ears. A bat is just such an animal. Some bats have very small eyes. But if you look at certain bats (like those that eat insects), you will see they have extra-large ears that move easily. Scientists now know that bats "see" by using what we call "echolocation" (EK-oh-low-KAY-shun). Here is how it works.
Bats make a sound that humans cannot hear. They send out sound waves that hit objects. A fraction of a second later, an echo comes back to their large ears. Bats not only hear the echo, but are able to tell how far away an object is, and in what direction. All of this happens so quickly that the bat is able to use the echo to locate the object, even though it may be far away. This is why it is called "echolocation."
Scientists have learned that bats, using echolocation, can fly through difficult places (like caves and forests) without any trouble. More importantly, bats use echolocation to hit an insect with sound waves, understand where it is, and catch it in mid-air! Bats are so good at doing this that it is almost impossible to trick them. In experiments, scientists threw small rocks in front of bats. The bats sent out sound waves and "saw" the rocks, but did not try to eat them as they would a flying insect. Somehow, bats are able to tell by the echoes whether or not the object is something good to eat!
God has designed creatures in the animal kingdom very well—so that they can survive. Man has learned much from the animals that God made—and we still have much more to learn!